Distortion profile says you probably don't want to use it below 200Hz, maybe 300Hz, which means that the huge excursion is pretty much irrelevant. Nice looking driver as far as it goes, but at almost $300 it's not an obvious value proposition - at least at first glance it doesn't have the special unique niche that the 6.5 fills.
I just got a set of VM752’s as part of 3 way speaker I am designing for a friend. Never have I ever held such heavy driver - it’s 22lbs and about the size of a very heavy 8in woofer. But it’s just a midrange.
Just look at how big it was a compared to keyboard of my 15in laptop.
Just look at how big it was a compared to keyboard of my 15in laptop.
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Sensitivity makes sense. This is a driver designed for small cabinets, passive radiators and low bass. Can't do that without low sensitivity. This is exactly the same parameter balancing that the 6.5" has so it's hardly surprising.
Peaking at the top end of the drivers range, when it comes to breakup, causing a peak in distortion at the same frequency (5kHz) but this isn't really a problem. Even small neo tweeters can go down to 3kHz and you've no reason to cross it higher for good off axis.
Distortion profile says nothing of the sort. All bass drivers show increasing distortion as frequency decreases. Look at the PTT6.5 on hificompass, it too shows rising distortion with decreasing frequency from about 300Hz.
The purifi measurements are done at 94dB, this is loud! Still by 100dB at 125Hz we're talking less than 1% distortion. This is significantly better than any of the other 4" drivers hifi compass has measured and better than some of the 5" drivers too.
It will be nice to see third party measurements for this driver, but in a small stand mount with something like the DXT from SEAS...this will make for a very capable tiny speaker.
The pricing is still prohibitive though.
Well, as erniem says this only makes sense as a desktop monitor where you absolutely can't go bigger and for whatever reason don't want to add a sub. Or maybe a hypothetical uber-high-end soundbar. My comment was aimed at using it as a midrange in a 3-way, which was my initial thought as to why you'd want something smaller than the 6.5.
So, $300 to anchor a 4" standalone desktop monitor seems like a market so limited as to almost not exist. Even at volume pricing, this would seem to result in $2k-$3kUSD for a 4" monitor and it's hard to see that working. Genelec + good sub would be less expensive, possibly by a fair bit.
I guess it's inevitable that someone like Totem (do they still exist?) is likely to come out with 'the best mini-monitor EVAH!!!' and charge $10k for it.
I just got a set of VM752’s as part of 3 way speaker I am designing for a friend. Never have I ever held such heavy driver - it’s 22lbs and about the size of a very heavy 8in woofer. But it’s just a midrange.
Just look at how big it was a compared to keyboard of my 15in laptop.
That's massive. What are the other drivers? Did you take any measurements of the Volt?
Not yet but will do so as I will design a passive crossover for it.
Tweeter will be a RAAL and woofer is TBD but leaning towards dual SBA Papyrus 7in in a tapered TL.
Looking forward to hearing the legendary sound of this British made 3in soft dome mid. (Although fabric, the dome is quite stiff like a paper driver). I don’t know how this thing manages to weigh so much. I think a Neodymium design would be welcome.
My PRV 5MR450NDY is about same sensitivity and similarly feels stiff but 1/10 the weight.
Tweeter will be a RAAL and woofer is TBD but leaning towards dual SBA Papyrus 7in in a tapered TL.
Looking forward to hearing the legendary sound of this British made 3in soft dome mid. (Although fabric, the dome is quite stiff like a paper driver). I don’t know how this thing manages to weigh so much. I think a Neodymium design would be welcome.
My PRV 5MR450NDY is about same sensitivity and similarly feels stiff but 1/10 the weight.
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I had hoped that the PTT4.0 would share the nice, smooth high end roll-off and ultra-low distortion of the PTT6.5, extending it up to 5k or so. Oh well. At this point, my best alternative is the SB12 or SB15, but I guess I'm leaning even more towards looking for a tweeter solution that goes below 2k with similarly low distortion. Perhaps a modified or DIY waveguide (to incorporate a grill) with the T25B. Or, perhaps it's time to reconsider the ESS large Heil.
Or, perhaps the MD60N will have super low distortion.
Or, perhaps the MD60N will have super low distortion.
mainframe99, you mentioned your Bliesma is lacking a little at the top end. did it open up in the last 2 weeks?
For my build, I was going to get a Transducer Lab ceramic but the seller pointed out an issue with one of the units so I end up getting a pair of Bliesma T25B6 instead. After putting on I also notice the top end is lacking some extension, lacking some "air". I am just wonder if that's the best I can expect or does some burn in eventually opens it up.
Having said that, it is much better than the B&W tweeter that I had before.
HI Paul
Which SB12 or SB15 are you considering?
I am also looking at the Bliesma, but not sure where to get a pair from? Unavailability and of course the cost are the major bottleneck...
Don't think the MD60N is available yet... But the Satori TW29BNWG-4 Beryllium Dome Tweeter with Waveguide is, but it's also at the ultra expensive end
I would probably go with the CAC series. I'd prefer the size and high frequency extension of the SB12, but I suspect the SB15 might have better distortion. So, I'm not sure.
I would buy the Bliesma from Solen. My experience of buying a pair of TL N26MGR-As from them went fine.
The TW29BNWG-4 is out of my budget.
I REALLY liked the Spirit Winds when I heard them at InDIYana. Perhaps I should go with the SS 9900 crossed over as low as reasonably possible. Tough decisions.
I am currently working on the XO for a SB12CAC in MTM. The response is really smooth and would allow for easy XO to a small ribbon, or basically any tweeter. I am liking it a lot. I don't have the CAC15, but Craig and Jim Liked it a lot. Cross at 1k to the Purifi would keep distortion in check. I am crossing at 3.7k
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No Drama here anymore with top end anymore. The bliesma/purifi combo is an absolute laser cutter into the mix. Never heard anything else like it. An extremely revealing speaker.